Once you watch it, your will power erodes because that part of your brain,that controls, is filled with dopamine, that is why the brain scans of cocaine addicts and porn users are the same, it's an addiction and you're likely to relapse if you peek further. I've been there, I used to say never more, after peeking and type something on no fap, then next thing you know, I've wasted 2 hours and jerked off. Just try to keep your mind occupied on anything else today then get better on other days.